Java 建造师故障排除
以下是我的项目:Java 建造师故障排除,java,constructor,this,Java,Constructor,This,以下是我的项目: package myProjects; import java.awt.GridBagConstraints; import javax.swing.JComponent; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JLabel; import javax.swing.JTextField; import javax.swing.JButton; import java.
package myProjects;
import java.awt.GridBagConstraints;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JButton;
import java.awt.*;
public class GeometryEquationSolver extends JFrame{
JPanel mainPanel;
JTextField eq1Text, eq2Text;
JButton enterButton, clearTextButton;
public static void main(String[] args) {
new GeometryEquationSolver();
}
public GeometryEquationSolver(){
this.setSize(340, 140);
this.setTitle("Equation Solver");
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
mainPanel = new JPanel();
mainPanel.setLayout(new GridBagLayout());
addItem(new JLabel("Equation 1"), 0, 0, 1, 1);
addItem(new JLabel("Equation 2"), 2, 0, 1, 1);
eq1Text = new JTextField(10);
addItem(eq1Text, 0, 1, 1, 1);
eq2Text = new JTextField(10);
addItem(eq2Text, 2, 1, 1, 1);
addItem(new JLabel("="), 1, 1, 1, 1); // Just the "=" for looks.
enterButton = new JButton("Enter");
enterButton.addActionListener(e->{
Equation eq1 = new Equation(eq1Text.getText());
});
addItem(enterButton, 0, 2, 1, 1);
clearTextButton = new JButton("Clear");
clearTextButton.addActionListener(e->{
eq1Text.setText(null);
eq2Text.setText(null);
});
addItem(clearTextButton, 2, 2, 1, 1);
this.add(mainPanel);
this.setVisible(true);
}
private String[] rawData;
private String[] splitEq(String eq){
rawData = eq.split("");
return rawData;
}
private void addItem(JComponent c, int x, int y, int width, int height){
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.gridwidth = width;
gbc.gridheight = height;
gbc.weightx = 100.0;
gbc.weighty = 100.0;
gbc.fill = GridBagConstraints.NONE;
mainPanel.add(c, gbc);
}
}
class Equation{
public enum opperation {add, sub, mult, div};
public opperation opper;
public String eq;
public Equation(String eq){
this.eq = eq;
opper = opperation.add;
this.Equation(this.eq, opper);
}
public Equation(String eq, opperation opper){
}
}
我的问题出现在班级方程式中。在第一个构造函数中,我必须执行以下命令:
this.Equation(this.eq, opper);
我得到了这个错误:
类型方程的方法方程(字符串、方程.操作)未定义
我正在尝试在第一个构造函数之后调用构造函数。有人知道如何解决这个问题吗?正确的语法应该是
this(this.eq,opper)代码>。但是,由于这一行必须是构造函数代码中的第一行,因此它将成为this(eq,opoperation.add)代码>
因此,您的构造函数最终将如下所示:
public Equation(String eq){
this(eq, opperation.add);
this.eq = eq;
opper = opperation.add;
//this.Equation(this.eq, opper);
}
如果在调用其他构造函数之前绝对有必要执行一些代码,这可能会有所帮助。如果您想从构造函数调用构造函数,请参考
下面是可以工作的代码
public class Equation {
public static enum opperation {add, sub, mult, div};
public opperation opper;
public String eq;
public Equation(String eq){
this(eq, opperation.add);
this.eq = eq;
opper = opperation.add;
}
public Equation(String eq, opperation opper){
}
}